1. Field of the Invention
The present invention relates to a fusible link used for electrical circuits of an automotive vehicle or the like.
2. Background Art
An automotive vehicle is arranged with various types of electrical equipment. In electrical circuits to supply electrical power from a battery to the electrical equipment, a fusible link is mounted to serve as a fuse device to protect the circuits from an overcurrent. Such an art is disclosed, for example, in Japanese Patent Application Laid-open No. 2004-127698.
The fusible link has a connection plate, a fusible portion continuous with one side of the connection plate, and a terminal continuous with the fusible portion. The fusible portion and the terminal constitute a fuse element. The fuse element is continuous with the connection plate to define a fuse circuit. The fuse circuit is received in a housing.
In the housing, a plurality of the fuse circuits are layered with a space therebetween. Each fuse circuit is electrically connected to each of a plurality of electrical instruments or machines. Thereby, the single fusible link can manage collectively the electrical instruments or machines.
The fusible link is received in a fuse box or in a junction box accommodating various electrical circuit units within a vehicle body. This provides fuses in electrical circuits from a battery to the electrical instruments or machines.
The housing of the fusible link has a window to see the inside of the housing. Through the window, the state of fusible portions of the fuse circuits can be are checked. When a fusible portion is fused by an overcurrent running in one of the electric circuits, the fusible link is replaced by a new one to enable conduction of the circuit.
The fusible link can be is easily replaced when the fusing portion is fused so that the fusible link is utilized as a large current fuse in various fields or machines including automotive vehicles.
The fusible link is disposed at a position where the electrical circuits are concentrated. Therefore, it is desirable that the fusible link itself is compact. Thus, the fuse circuits are layered with a smaller space therebetween in the housing so that the housing has a smaller depth.
However, the smaller space between the fuse circuits causes the fusible portions of the fuse circuits to come close to each other. Thus, when the fusible portion of one of the fusible portions is heated by an overcurrent, an adjacent fusible portion is also effected by the heat so that the adjacent fusible portion will have a less fusing time.
Therefore, a larger space between the fuse circuits is preferable to have a smaller effect on the adjacent fusible portion when the one of the fusible portions is heated by an overcurrent. However, this can not achieve a compact fusing link, requiring a larger depth housing.